I have changed the isolation code a bit. I have now 3 a4j:button s reRendering different parent levels of the datatable. Only the button, which rerenders the datatable direct, keeps the commandSortHeader working.

FYI: I get the same java script error for all h:commandLink s inside the persons form. Bute here I can work around it by using a4j:commandLink instead of h:commandLink. In case of the t:commandSortHeader, I have no possibility to influence the link rendering.